1. Field of the Invention
The present invention relates to an engine controller that controls operation of an engine in a hybrid vehicle including the engine and a motor, and specifically, to an engine controller for forced driving of the engine at inspection of the engine.
2. Description of the Related Art
Hybrid vehicles are divided into a type in which an engine may be a drive source of a vehicle (so-called “parallel hybrid vehicle”) and a type in which an engine may not directly be a drive source of a vehicle and mounted mainly for operation of a power generator (so-called “series hybrid vehicle”), and both can travel using only a motor as a drive source with the engine stopped.
The so-called parallel hybrid vehicle that can directly transmit the power of the engine to drive wheels generally travels using the engine as a main drive source during traveling, however, in the case where the power of the engine is not necessary at deceleration and downhill, at initial acceleration, or the like, the vehicle may travel with the engine stopped.
The so-called series hybrid vehicle in which the engine is used only for driving of the power generator charges a secondary cell by activating the power generator using the engine in the case where the remaining capacity of the secondary cell that supplies power to the motor becomes lower or the like, and stops the engine when the remaining capacity of the secondary cell is restored.
As described above, in the hybrid vehicles, even when the starter switch is in the operation state, the engine operates and stops according to the remaining capacity of the secondary cell and the traveling condition of the vehicles. In a vehicle using only an engine as a drive source, the engine continues to operate unless the starter switch is turned into the stopped state, and the hybrid vehicle is largely different from the vehicle using only the engine as the drive source in the above point.
In such a hybrid vehicle, as is the case of the vehicle using only the engine as the drive source, an inspection of the engine is necessary at regular intervals or failures. Since the engine mounted on the hybrid vehicle has basically the same configuration as that of an engine mounted on the conventional vehicle using only the engine as the drive source, the inspection method of the operation of the engine is performed in the same manner as the inspection method in the conventional vehicle.
As described above, the inspection of the operation of the engine is necessary even in the hybrid vehicle, and it is necessary to operate the engine in various operation states at inspection. However, as described above, the hybrid vehicle stops the operation of the engine when a predetermined condition that the remaining power of the secondary cell is sufficient or the like is satisfied. Therefore, depending on the charged state of the secondary cell or the like, the operation of the engine may not be maintained at inspection, and a problem arises in the inspection.
Accordingly, as a related technology conceived to maintain the operation of the engine and cause no problem in inspection, there is Japanese Patent No. 2982746. According to the technology, inspection state determination means for determining whether the inspection of the operation of the engine is performed or not is provided, and the operation of the engine is maintained in the state suitable for inspection regardless of the satisfaction of the operation stop conditions that characterize the hybrid vehicles.
Further, as a related technology conceived to maintain the operation of the engine in the state suitable for inspection, as shown in Japanese Patent No. 3991498, there is a technology of performing the operation of the engine when a predetermined operation set for inspection is detected.
In Japanese Patent No. 2982746, in order to perform the inspection of the engine, the inspection state determination means for determining whether the inspection of the operation of the engine is performed or not is provided, and an inspection tool for turning an inspection terminal dedicated for vehicle into the inspection state is necessary.
Further, in Japanese Patent No. 3991498, the inspection state can be determined using the inspection state determination means by performing a special operation and an inspection can be performed without the inspection tool, however, it is necessary to acquire a special operation procedure in addition to the normal operation for starting up the vehicle. Further, it is necessary to perform a special operation in a driver's seat when the inspection is performed and necessary to enter the driver's seat to perform the special operation at each time of the performance of the inspection of the engine. Accordingly, there are problems of poor work efficiency because it is impossible to perform an inspection without knowledge of the special operation procedure for starting up the vehicle at the inspection in a dealer or the like, and it is necessary for a worker to enter the driver's seat for performing the special operation at the shipping inspection in the factory.